Engine cooling



Aug. 25, 1931.

A. B. REAVIS ENGINE- COOLING Filed July 27, 1929 Fur-J.

INVENTOR WITNESS Fig.4".

Patented Aug. 25,- 1931' UNITED STATES PATENT OFFICE EECTRIC & MANUFACTURING COMPANY, A CORPORATION OF PENNSYLVANIA ENGINE COOLING Application filed 'Jul 2?,

invention relates to cooling systems for internal combustion enginesand it has er means for. forcing air to pass through the to control heat exchanger and about the tubular elements thereof, the blower means comprising a casing having its discharge end arranged to discharge air through the heat exchanger and a motor-operated propeller arranged in the casing. With apparatus of this character, it is desirable that the cooling unit shall be so arranged that cooling liquid returning to the engine jacket space shall be at as nearly uniform a temperature as possible; and a more particular object of my. invention is to provide a unit of the character referred-to having this capability.

Itis, of course, well known to employ thermostatic control of shutter means for automobile radiators in order to control the temperature of jacket water returningto the engine acket space. In an arrangement of this character, the shutter means merely operates the quantity" of air admitted to or entering the radiator. My improvedcooling system is different in that a propeller blower is used to force air through the heat exchanger, the discharge end of such blower being connected to the latter, and in that I provide, with a combined blower and heat exchanger unit, thermostatic means responsive to'temperature-of the liquid returning to the engine for varying the capacity of the blower means to deliver air to the heat exchanger. This variation in delivery capacity may be efi'ected either by varying the pro eller motor speed or by spillin a portion 0 the air.

These and other ob ects are effected by my invention, as will be apparent from the following description and claims, taken in conor circulating propeller blow from the tubular 1929.v Serial No. 381,644.

nection' with the accompanying drawin s, forming a part of this application, in whic Fig. 1 is a diagrammatic view showing my improved cooling means with thermostatic control of the propeller motor;

Fig. 2 is a view, similar to Fig. 1, but showing thermostatic control of s illing means associated with the blower device;

- Fig. 3 is a detail view of the shutter and the operating means thereforof Fig. 2; and, ig. 4 is a view, similar to Fig. 2, but showing, in addition, ling communication between the blower casing and the heat exchanger.

In Fig. 1, I show an internal combustion engine 10 having inlet and outlet cooling liquid passages 11 and 12 for the jacket space or spaces of the engine, the passages 11 and 12 being connected by tubular or cellular elements 13 of the heat exchanger, at 14, the lat-' ter embodying a suitable casing 15, which has connected thereto the diverging end 16 of the converging-diverging casin means for causing air to be gi the casing through the heat'exchanger and about thetubular elements 13 thereof. I The blower means includes a propeller 18 arranged substantially at the throat portion of the converging-diverging casing 17, the propeller being operated b a suitable motor 20. .It will be obvious that the propeller causes air to be translated through the converging-diverging casing and then through.

the heat exchanger, suchair absorbing heat or cellular elements 13 forming a part of the 'fluid circuit including the passages 11 and 12 and the ump 21 for enforcing circulation of liquid t rough such circuit. If desired, as shown in, the'draw ings, the flow area of the heat exchanger and the dischargeiarea of the casing 17 may be coordinated to secure the best operation. On account of the space occupied by the tubular or cellular elements of the heat exchanger, it is obvious that the over-all flow area of the latter, including the space occupied by the tubular or cellular elements should be relatively larger than the flow area of the dischargev end of the casing 17 in order to re- 17 of blowerscharged from shutter means for controlduce the resistance to flow of air thereof a rheostat arranged in the field circuit of the shunt motor 20. With this arrangement, an increase intemperature of the returning liquid causes an increase in the field circuit resistance, which results in an increase in speed of the motor 20. A decrease-in the returnin cooling li uid, temperature results in a ecrease in t e speed. of the motor. Therefore, the motor speedis made dependent upon the temperature of the. cooling liquid and the speed may be so controlled that the blower means serves to deliver suflicient:

quantity of air to the heat exchanger to maintain a substantially uniform returning cooling liquidtemperature.

In Fig. 2, I show apparatus somewhat similar to that shown in Fig. -1 except that the motor 20a for the propeller 18 may be of the constant speed t pe and air is spilled from the conver'gmgiverging casing/17 in order to control the quantity of air delivered from the latter casing to the heat exchanger, at 14.

To this end, I show the converging diverging' casing 17 provided with an opening 24 close by aseries of shutters 25 having pivots at their ends su ported by the casing 17 The shutters may e turned simultaneously in the same direction to open the opening 24 to a desired extent, or they may be turned in the other direction to close such opening).

e assosuitable operatin mechanism may ciated with the s utters 25 to secure simultaneous opening and closing movementsthereof. In Fig. 3, I show-the shutter elements 25 provided with segmental sprocket elements 26 engaging a sprocket chain 27, the latter havin one end connected to a spring 28 supporte from a stationary support 29.

- The other end of the sprocket chain is operatively connected to the thermostat 22a. In operation, if the temperature of the returning cooling liquid should become too high,

- the thermostat 22a is effective to move the shutters 25 in a closing direction; and,if the temperature declines below a predetermined point, the spring 28 is efi'ective to move the shutters 25 in an opening direction, whereby the quantity of air delivered to the heat exchanger may be varied'in order to carry ofi sufliclent' heat to maintain a substantially constant temperature of returning cooling liquid.

In Fig. 4, I show the converging-diverging casing 17 equipped with shutter means-as shown in Figs. 2 and 3 together with additional' shutter means arran ed between the heat exchanger and the disc arge end of the converging-diverging casing 17 The latter shutter means embodies cooperating shutter elements .31 having arms 32 connected to an operating link 33, the latter being moved in one direction or theother'by'the thermostat 22b. The thermostat'is also connected to a sprocket chain '27 engaging sprocket elements 26, as shown in Fig. 3,.a'nd having its upper end connected to a spring 28. The relation--.

ship of the operating means for the shutters 25 and 31 is such that as the. shutters 2'5'open the shutters 31 close and vice-versa.

From the foregoing, it will be apparent that I have devised a propeller blower cooling unit suitable for use with the cooling circuit of an internal combustion engine such that the propeller blower is controlled or regulated in order to deliver to the heat exchanger sufiicient air to maintain a substan-; tially constant returning cooling liquid temperature. In theform shown in Fig. 1, the required quantity of air passing from the propeller blower to the heat exchanger" to a give a desired returningliquid temperature is secured by adjustment of the motor speed.

In Figs. 2 and 3,,Variation in delivery of air.

from the blower to. the heat exchanger is secured by adjustably spilling a; portionof the air; A propeller type suitably designed housin is -highly efiicient and the power consumptiomcorresponds to the demand in all forms shown. Wherethe motor speed is varied, the power consumed depends on the speed; and, wherethere is spilling, the power required the propeller diminishes -WhileI have shown In .invention- 1n several forms," it will be 0 vious to those skilled in the art that it is not so limited, but is susceptible of various other changes .and modifications, without departing from the spirit thereof, and I desire therefore, that only such limitations shall be placed thereupon as are imposed are specifically set claims; What I claim is:

1. In a cooling system an internal combustion engine, the combination of a liquid'circuit including the engine jacket space, inlet and; outlet passages connected to the j aoket space, and a heat exfor operating for jacket liquid of blower having a f by-the prior art or as forth in the appended having a divergent portion with its discharge end'arranged to discharge air through the heat exchanger, a propeller in the casing at the entrant end of'the divergent portion,

and means responsive to temperature of liquid leaving the heat exchanger for connected to the jacket space, a heat exchanger connecting the inlet and outlet passages, and a pump forenforcing circulation of liquid in the circuit; and propeller blower means for furnishing cooling air to the heat ex changer including a converging-diverging casing having its diverging end arranged to discharge air through the heat exchanger,-a propeller in the region of the casing where the converging and diverging portions thereof join, and means responsive to temperature of liquid leaving the heat exchanger for controlling the capacity of the blower means to deliver air to the heat exchanger.

. 3. In a coolin system for jacket liquid of an internal comoustion engine, the combination of a liquid circuit including the engine jacket space, inlet and outlet passages connected to the jacket space, a. heat exchanger embodying a casing and tubular elements and the tubular elements affording communication between the inlet and outlet passages, and a pump for enforcing circulation of liquid in the circuit; and propeller blower means for furnishing cooling air to the heat exchanger including a converging-diverging ea sing having its dlverging end connected to the heat exchanger casing and arranged to discharge air through the heat exchangerand about the tubular element thereof, a

propeller in the region of the casingwhere the converging and diverging portions thereof join, and means responsive to temperature of liquid leaving the heat exchanger for controlling the capacity of the blower means to deliver air to the heat exchanger. v

4. In a cooling system for jacket liquid, of an internal combustion engine, the combination of a liquid circuit including the engine jacket space, inlet and outlet passages connected to the jacket space, a heat exchanger connecting the inlet and outlet passages, and a pump for enforcing circulation of liquid in the circuit; and -propeller blower means for furnishing cooling air to the heat exchanger including a converging-diverging casinghaving its diverging end arranged to discharge air through the heat exchanger, a propeller arranged substantially in the throat portion. of said casing, an electric motor arranged at the upstream sideof the propeller for driving the latter, and means responsive to temperature of liquid leaving the heat exchanger for controlling the speed of said motor.

-5. In apparatus forcooling internal combustion engine jacket liquid, the combination of a heat exchanger including a casing and tubular elements, the jacket liquid being arranged to pass through and propeller blower means for furnishing coohng air to theheat exchanger, said-pro-' peller blower means including a convergmgdiverging casing having its diverging end connected to one end of the heat exchanger casing and arranged to discharge air through the heat exchanger and about-the tubular elements thereof, a propeller in the region of said casing wherethe converging and diverging portionsthereof join, a motor for driving the propeller, and means responsive to the temperature of liquid leaving the heat exchanger for controlling the speed of said motor.

.In testimony whereof, I have hereunto subscribed my name this 23rd day of July, 1929. i

ANDREW B REAVIS.

the tubular elements, 

